Communities of larger fungi of ombrotrophic bogs in West Siberia N.V. Filippova1 and M.N. Thormann2 1Yugra State University, Khanty-Mansiysk, Russia 2Aquilon Environmental Consulting Ltd., Edmonton, Canada _______________________________________________________________________________________ SUMMARY Bogs are common ecosystems in the Taiga of West Siberia. Little is known about mycological diversity in these important ecosystems. This article summarises the results of a two-year study of the macrofungi in two bogs near the town of Khanty-Mansiysk. Sporocarps were collected in 20 plots (about 300 m2) established in Mukhrino Bog as well as during random walks in Mukhrino Bog and Chistoe Bog in the late summer– autumn of 2012 and 2013. The plots were established in two common bog habitats representing the Ledo- Sphagnetum fusci (LS) and Scheuchzerio palustris-Sphagnetum cuspidati (SS) plant community associations. A total of 59 distinct fungal taxa were collected from the two bogs, with the LS association having a higher species richness and diversity than the SS association (50 taxa vs. 16 taxa and 30–40 taxa per 1000 m2 vs. 6– 10 taxa per 1000 m2, respectively). Each of the two plant community associations has its own characteristic fungal taxa, with the LS association having 13 characteristic taxa and the SS association having five. Nearly two thirds of the fungal taxa are saprotrophic, mainly of Sphagnum spp., while others are mycorrhizal, mainly with Pinus spp. Most taxa were collected fewer than ten times during the study period and, hence, are considered rare and may need to be recognised for conservation programmes in this region. KEY WORDS: ecology of fungi; fungal diversity; macrofungi; oligotrophic bog; peatland _______________________________________________________________________________________ INTRODUCTION constituents of peat vary between different peat layers, and Christensen & Whittingham (1965) have Peatlands, especially bogs, are common ecosystems shown that fungal communities differ between in West Siberia, where they stretch almost mineral and organic soils. From a functional continuously across the central and northern Taiga perspective, the role of fungi in the decomposition region (Walter 1997). The coverage of peatlands in of organic matter was thought to be less important West Siberia has been estimated at 68.5 × 106 ha than that of bacteria (Waksman & Purvis 1932, (about 24.5 % of the total area). In the Middle Taiga Zaguralskaya 1967), but this view has shifted over zone, peatland reaches its maximum coverage, about the past decade. Fungi are now thought to be 34.5 % (Peregon et al. 2009). The classification of significant amongst the decomposer communities in peatlands in this region is based on their trophic peat, particularly in the oxic peat horizon, the status and dominant plant communities (Liss et al. acrotelm (Thormann & Rice 2007). Fungi also occur 2001); all oligotrophic peatlands include 14 types of in the anoxic peat horizon, the catotelm, but they biogeocoenoses. Subsequently, Lapshina (2010) grow only slowly in this horizon due to lack of developed a floristic classification of peatlands for oxygen or low oxygen concentrations (Golovchenko the south-eastern part of West Siberia, identifying & Polyanskaya 1999, Kurakov et al. 2008, Grum- two community classes for ombrotrophic vegetation, Grzhimaylo 2013). Consequently, most of the namely: Scheuchzerio-Caricetalia nigrae and fungal biomass occurs in the acrotelm. It has been Oxycocco-Sphagnetea. While floristic work on West assessed using a variety of methods including Siberian peatlands has progressed considerably, luminescent microscopy (Golovchenko et al. 1993, comparatively little is known about the mycological Golovchenko et al. 2002), counting of colony- communities of peatlands in this region. forming units (Zaguralskaya 1967, Thormann et al. The fungal communities of peatlands have been 2001) and by phospholipid fatty acid concentration studied for more than 50 years. At the beginning of (Sundh et al. 1997, Jaatinen et al. 2007, Andersen et the twentieth century, peat was thought to be sterile. al. 2010). About 600 fungal taxa have been reported Since then, Waksman & Purvis (1932) have shown from peatlands, with a similar taxonomic richness of that fungal communities as well as fungal viability ascomycetes and basidiomycetes (Thormann & Rice and the ability of fungi to decompose the 2007). The commonest studies of fungi in peatlands Mires and Peat, Volume 14 (2014), Article 08, 1–22 http://www.mires-and-peat.net/, ISSN 1819-754X © 2014 International Mire Conservation Group and International Peat Society 1 N.V. Filippova & M.N. Thormann LARGER FUNGI OF OMBROTROPHIC BOGS IN WEST SIBERIA have been incidental surveys for macromycetes, components in the West Siberian plain. To that end, which have contributed most of our knowledge detailed mycological surveys were initiated in about peatland basidiomycetes (e.g. Salo 1979, several peatlands near Khanty-Mansiysk in the early Lange & Lange 1982, Redhead 1989, Salo 1993, 2000s, focusing on phylloplane yeasts of Sphagnum Wurtzburger et al. 2004, Stasinska 2011); whereas spp. and vascular plant species (Kachalkin 2010), our knowledge of peatland ascomycetes arises micromycete communities of different peat layers mostly from culture-based research (e.g. Thormann (Grum-Grzhimaylo unpubl. data), discomycetes of et al. 2001, 2003; Golovchenko et al. 2002, vascular plant and woody litters (Filippova 2012), Kachalkin et al. 2005, Grum-Grzhimaylo 2013). and lignicolous macromycetes of common woody There are records of about 800 fungal taxa in the substrates in treed bogs (Filippova & Zmitrovich Khanty-Mansiysk region (Filippova 2010), of which 2013). Most recently, autecological notes on several about half are lignicolous taxa and about 300 taxa rare species have been published (Filippova & are members of the Agaricales, known from forest Bulyonkova 2013). ecosystems. Peatland-specific taxa are relatively The objectives of this study were to describe the unrecorded, however. Fungal surveys are important macrofungal communities in two bogs in West components of regional biodiversity inventories, as Siberia in an effort to gain a better understanding of fungi contribute significantly to the biodiversity of mycocoenoses and the roles of fungi in these an ecosystem. Ultimately, having a better important ecosystems, particularly in relation to the understanding of the biodiversity of fungi at local or potential impacts of fungi on the global carbon regional scales facilitates the development of cycle. conservation programmes that aim to maintain biodiversity at those scales. Macromycetes have been investigated in METHODS numerous peatlands, and about 300 taxa have been reported globally (Thormann & Rice 2007). No The study area more than 150 taxa have been reported from a single The study region is in the vicinity of the town of peatland class, and treeless bogs generally have a Khanty-Mansiysk in the central Taiga of West less diverse fungal flora than treed fens. For Siberia. The climate is subarctic with short, cool example, Favre (1948) reported about 400 taxa from summers and long, cold winters. Snow cover different peatlands in the Jura mountains and persists for about 180 days in this region. The mean Stasinska (2011) recorded a total of 191 fungal annual temperature is –1.3 °C, the mean temperature species in the raised and transitional bogs of of the coldest month (January) being -19.8 °C and Pomerania (Poland), including 12 taxa from a the temperature of the warmest month (July) being Rhynchosporetum albae community class, 15 from a 18 °C. The total annual precipitation is 553 mm, Caricetum rostratae community class, 102 from a with 70–80 % of the total annual precipitation Vaccinio uliginosi-Pinetum community class, and falling in the summer months (Bulatov et al. 2007). 121 from a Vaccinio uliginosi-Betuletum pubescentis community class. In a study of two Study sites mountain bogs in the Czech Republic, Holec (1997) Two bogs were selected for this study (Figure 1). described two fungal communities with 21 and 19 Mukhrino Bog (60.892 °N, 68.674 °E) is on an species. About 100 taxa were reported from ancient terrace of the Ob and Irtysh Rivers in the peatlands in Central Finland (Salo 1979), and 70– northern part of the Kondinskiy peatland district, of 100 taxa were reported from different peatland which about 57 % is peatland covered (Ivanov & classes in Romania (Tanase 2000, Chinan & Tanase Novikov 1976, Liss et al. 2001). This bog covers an 2009, Chinan 2011). Functionally, the macromycete area of about 10 km2 and is dominated by community in peatlands consists primarily of ombrotrophic plant communities, with transitional ectomycorrhizas and saprotrophs of various organic plant communities only at the edges of the bog and constituents such as Sphagnum, peat and vascular along watercourses. Chistoe Bog (61.059 °N, plant litters (Favre 1948, Thormann & Rice 2007, 69.466 °E) is on an ancient terrace of the Ob River Stasinska 2011). in the northern part of the Salymo-Yuganskiy Because many of the fungi found in peatlands are peatland district which is about 34 % peatland saprotrophic (e.g. Thormann 2006, Thormann & covered (Ivanov & Novikov 1976, Liss et al. 2001). Rice 2007), it is important to understand their The area of this bog is about 3 km2 and it is potential impacts on the carbon dynamics of dominated by a complex of ombrotrophic and peatlands, which form significant landscape